Middle+Ages+-+18th+C+-+1700's+YAL

Literature was tied to religion and to morality. The first book published specifically for children was called //The Book of Courtesy// in 1477. Aesop's fables were originally published for adults. The audience shifted to children because of the lessons taught with each tale. The thematic elements around the original literature came from the societal idea that children were "deficient" adults.

In the 17th century, adolescent texts were based on Christianity. Both examples from the text focus on the message of not conforming to societal morality God will punish you and you will go to hell. Additionally, two major works that help define adolescent literature in the 1700's were //The Life and Strange Surprising Adventures of Robinson Crusoe// and //Gulliver's Travels//. John Newbery's began publishing literature specifically for young adults in the mid-1700's, but it was still not accepted and took a long time to gain popularity.

https://publicdomainreview.org/2014/05/14/in-the-image-of-god-john-comenius-and-the-first-childrens-picture-book/